The invention relates to a process for producing balls of the generic by a rolling operation and to an associated apparatus.
DE 336 151 discloses a ball rolling mill with two rolling jaws which can be displaced relative to one another. In this document, the rolling jaws are formed, on the one hand, by a rolling roll and, on the other hand, by a stationary segment which engages around part of the rolling roll. The shaping grooves are provided on the circumferential surface of the rolling roll and on the hollow surface of the segment. The two jaws are located displaceably with respect to one another such that the U-shaped shaping grooves are located opposite one another on the opening side. A shaping channel is formed as a result, a blank being rolled, as a result of the displacement of the channel walls relative to one another, on its passage through said shaping channel. The known apparatus also has a feed device for the purpose of feeding blanks, which are cut off from a wire strand by means of a cutting tool, via a feed channel, to an opening of the shaping channel. In the known apparatus, the cylindrical blanks, which are located one behind the other in a guide channel, are separated by a spoked wheel and fed into the opening of the shaping channel as a result of gravitational force. The operation of rolling the cylindrical blank into the form of a ball takes place by way of a shaping channel which tapers vertically in the rolling direction.
DE 202 032 likewise discloses a process for producing balls from a cylindrical metal rod, without any waste, as well as an associated apparatus. In this document, a cutter is used to cut off a blank, which is provided with a V-shaped groove, from a wire strand and then to feed it, by means of a feed device (not described in any more detail) into a shaping channel. In this document, the shaping channel is formed by the interspace between two rolls which are driven in the same direction of rotation.